org.springframework.beans.factory.xml.DelegatingEntityResolver Maven / Gradle / Ivy
/*
* Copyright 2002-2019 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.beans.factory.xml;
import java.io.IOException;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.springframework.lang.Nullable;
import org.springframework.util.Assert;
/**
* {@link EntityResolver} implementation that delegates to a {@link BeansDtdResolver}
* and a {@link PluggableSchemaResolver} for DTDs and XML schemas, respectively.
*
* @author Rob Harrop
* @author Juergen Hoeller
* @author Rick Evans
* @since 2.0
* @see BeansDtdResolver
* @see PluggableSchemaResolver
*/
public class DelegatingEntityResolver implements EntityResolver {
/** Suffix for DTD files. */
public static final String DTD_SUFFIX = ".dtd";
/** Suffix for schema definition files. */
public static final String XSD_SUFFIX = ".xsd";
private final EntityResolver dtdResolver;
private final EntityResolver schemaResolver;
/**
* Create a new DelegatingEntityResolver that delegates to
* a default {@link BeansDtdResolver} and a default {@link PluggableSchemaResolver}.
* Configures the {@link PluggableSchemaResolver} with the supplied
* {@link ClassLoader}.
* @param classLoader the ClassLoader to use for loading
* (can be {@code null}) to use the default ClassLoader)
*/
public DelegatingEntityResolver(@Nullable ClassLoader classLoader) {
this.dtdResolver = new BeansDtdResolver();
this.schemaResolver = new PluggableSchemaResolver(classLoader);
}
/**
* Create a new DelegatingEntityResolver that delegates to
* the given {@link EntityResolver EntityResolvers}.
* @param dtdResolver the EntityResolver to resolve DTDs with
* @param schemaResolver the EntityResolver to resolve XML schemas with
*/
public DelegatingEntityResolver(EntityResolver dtdResolver, EntityResolver schemaResolver) {
Assert.notNull(dtdResolver, "'dtdResolver' is required");
Assert.notNull(schemaResolver, "'schemaResolver' is required");
this.dtdResolver = dtdResolver;
this.schemaResolver = schemaResolver;
}
@Override
@Nullable
public InputSource resolveEntity(@Nullable String publicId, @Nullable String systemId)
throws SAXException, IOException {
if (systemId != null) {
if (systemId.endsWith(DTD_SUFFIX)) {
return this.dtdResolver.resolveEntity(publicId, systemId);
}
else if (systemId.endsWith(XSD_SUFFIX)) {
return this.schemaResolver.resolveEntity(publicId, systemId);
}
}
// Fall back to the parser's default behavior.
return null;
}
@Override
public String toString() {
return "EntityResolver delegating " + XSD_SUFFIX + " to " + this.schemaResolver +
" and " + DTD_SUFFIX + " to " + this.dtdResolver;
}
}